when i am viewing mozilla internal pages such as this one, i want them to be dark? i am not super computer savvy and feel that this should be rather easy

Firefox can use a dark theme for the browser UI, but some internal/support pages still follow separate page styling. Try these in order: Settings > General > Language and Appearance > Website appearance = Dark, then open Add-ons and Themes and choose a dark theme. If a specific internal page still stays light, set Settings > General > Fonts and Colors > Colors > Override the colors specified by the page to Always, but test it carefully because that can make some sites harder to read.

This article may explain why extensions and such may not work on sites restricted by Mozilla. https://support.mozilla.org/en-US/kb/quarantined-domains